Homebrew PCBs

Stefan,

>Isn't 6 minutes a bit long...

    One common reflow profile calls for an initial gradual heat 
(approx 2C/sec) up to 125C, then a slow increase (about 1C/sec) up to 
175C, followed by rapid heating to soldering temp (220-250C) and a 
10-15 sec dwell for full reflow.  Altogether about 2.5 mins and then 
cooling down.  Co-incidentally, this sounds like it would be a good 
profile for baking the ink also ;-?

    I reckon with some insulation (there is none currently) it should 
be achievable OK.  Elektor recommend 100W+ per litre of oven.  Mine is 
800W and 4 litres so should comfortably exceed these requirements. 
Stripping out most of the internal metalwork will also help.

>How do you plan to insulate it?

    Some time ago while building a heat-treatment muffle, I bought a 
large roll of refractory insulation, rather like rock-wool but good 
for 1800C.  I still have lots left, so I'll be using some for this 
project.

>I may want to isolate at least the electronics...

    Definitely!

Regards,

Philip.